- Fix pkg-plist to delete directories installed out of PREFIX (on /var)
How-To-Repeat: - Install www/oops and then deinstall it; notice that /var/log/oops and /var/run/oops directories are not cleaned up. This is because the @dirrmtry macro prepends PREFIX to its arguments; therefore, we need to reset PREFIX to '/' with @cwd for the @dirrmtry macro to work properly towards the end of the pkg-plist.